Balanced abrasive wheel.



J. O. SPENGE.

BALANCED ABRASIVE WHEEL.

APPLICATION FILED NOV. 15, 1913.-

Patented Mar. 2, 1915.

2 SHEETS-$HEET 1.

J. U. SPENUE.

BALANCED ABRASIVE WHEEL.

APPLICATION FILED NOV. 15, 1913.

1,130,210,, Patented Mar. 2, 1915.

2 SHEETS-SHEET 2.

6mm wuwkm 6 m ZWM U D STATMENT oFFioE. f

JOHN c. srnNcn' or woncn's'rna, mssacmrsnr'rs, Assnmon r0 NORTON comrnm'r,

or woncnsrnn, mssacnusn'rrs, A CORPORATION or massflcnusnrrs.

ranmironn A RASIV I t -or was neat: Y i'fRateatedMar. 2,31915.

Application filed November 15, 1913. ,Serial 80.801350.-

To all whom it may concern:

citizen of the United States, residing at. Worcester, in the county of Worcester and State of Massachusetts, have invented certain new and useful Improvements in Balanced Abrasive Wheels, of which the following is a specification. v

This invention relates to means for balancing abrasive wheels by securing at a point or points near the axis of rotation thereof a suitable Weight or weights rigidly secured so as to constitute practically an integral portion of the structure,so placed as to establish the balance, and so located that the center of gravity of said weight or weights substantially coincides with the central plane of the wheel, thereby producing a true or running balance of the wheel, as distinguished from a merely static balance. This result is attained by securing in the central opening of the wheel a hard metal center, preferably of iron or steel, so constructed as to contain one or more chambers, recesses, or pockets so located that a weight or weights, inserted therein, will lie wholly or largely within the lateral planes of the wheel, will be rotected from displacement by centrifugal force, and will have its center of gravity substantially in the central plane of the wheel.

In the drawings,Figure 1 is-a longitudinal section of a wheel showing a center provided with chambers, recesses, or pockets, and balancing weights secured therein; Fig. 2 is a transverse section of the wheel on the line 2-2 of Fig. 1; Fig. 3 is a partial longitudinal section of a modified form of center; Fig. 4 is a partial transverse section of the modification shown in Fig. 3; and Figs. 5 and 6 are respectively partial longitudinal and transverse sections of another modified form of center.

In Figs. 1 and 2, the center 11, preferably of cast iron, has an inner channel or groove 12 formed by undercut walls 13, and subdivided into a plurality of chambers14 by partitions 15, likewise undercut. The center 11 is secured in any usual manner in the wheel 10, and the wheel then tested as to its balance, for example, by the method described in U. S. Patent 982,629, dated January 24:, 1911. Melted lead to form weights 9, 9, is then poured into a selected chamber or chambers quantity suflicient to produce a true or running balance of the wheel,

In the modification shown in Figs. 3 and 4, the chamber -16 is an annular channel with undercut walls. The center is secured in the wheel, and after testing for balance as above noted, a movable weight or weights,-

17, sufiicient to establish the true or running balance 1s secured in the channel by any suitable means, as for example, a set screw,

or by a screw 18 that will expand the weight to tightly fit the undercut walls.

In the modification shown in Figs. 5 and 6, the center is transversely perforated as at 19, 19, the perforations having countersunk edges 20. After securing in the wheel and testing for balance, tightly-fitting plugs or weights 21, suflicient in number, are inserted 1n the perforations inf locations to give the desired running balance. The plugs or weights are held rigidly in position by the countersunk edges of the perforations.

In each of the above modifications, the balancing weight is suflicient to establish the true or running balance, and is so disposed that its center of gravity is substantially 1111118 central plane of the wheel, thereby malntaining a true or running balance of the wheel, and avoidingthe mechanical stresses or force couples which would result if the weight were located outside of the wheel.

The .wheel balanced in the manner herein described does not require rebalancing every time it is mounted on a wheel-sleeve, and remains in balance until the balance is destroyed by considerable wear. The hard metal center will maintain a given diameter of hole for a long period of time, and will not rapidly enlarge in diameter, or be easily injured as would a soft metal center or bushing.

It will be observed that in all of the above modifications, the mass of the center including that of the added weights, is uniformly distributed to an extent suificient to neutralize and correct the ununiformity in distribution of the mass of the abrasive, thus producing a true or running balance of the completed wheel.

I claim 2- ,1. An abrasive wheel having a balance weight rigidly secured in the central plane thlerelof, and near the axis of rotation of the w ee v 2. A balanced abrasive wheel having a balance weight within its lateral planes and near its axis of rotation, the central plane of said weight lying substantially in the central plane of the wheel. 4

3. In an abrasive wheel, a metal center containing a chamber or chambers located in the central plane of the wheel, and, a weight orweight's' in said chamber. or chambers.

4. In an abrasive wheel, a metal center or bushing rovided with one or more cham bers in t e central plane of the wheel, and a weight or weights rigidly secured therein and adjusted to balance said wheel.

5. In an abrasive wheel, a metal center or bushing provided with one or more chambers, a weight or wei hts immovably secured therein and adjuste to balance said wheel,

said weight or weights located between the lateral planes of the wheel. 6. A balanced abrasive wheel consisting of a shaped mass of abrasive, a metallic center secured therein, a weight or weights In testimony whereof I afiix center or bushing, said center having its mass ununiformly distributed and united tosaid mass of abrasive within its outer planes in such a manner as to secure a true or running balance of the wheel. 8. In an abrasive wheel, a center containmg an undercut chamber or chambers, said chamber or chambers opening toward the axis of the wheel and located in the central plane thereof, and a weight or weights rigidly secured in said chamber-or chambers. my signature in presence of two witnesses. I

JOHN C. SPENOE. Witnesses:

J. HERBERT JoHNsoN, ALFRED J. DUPRE. 

